Dust devils on Earth and Mars: Extension of particle threshold laboratory simulations

Abstract not available

Dust Devil Sediment Transport: From Lab to Field to Global Impact

The impact of dust aerosols on the climate and environment of Earth and Mars is complex and forms a major area of research. A difficulty arises in estimating the contribution of small-scale dust devils to the total dust aerosol. This difficulty is due to uncertainties in the amount of dust lifted by individual dust devils, the frequency of dust devil occurrence, and the lack of statistical generality of individual experiments and observations. In this paper, we review results of observational, laboratory, and modeling studies and provide an overview of dust devil dust transport on various spatio-temporal scales as obtained with the different research approaches. Methods used for the investigation of dust devils on Earth and Mars vary. For example, while the use of imagery for the investigation of dust devil occurrence frequency is common practice for Mars, this is less so the case for Earth. Modeling approaches for Earth and Mars are similar in that they are based on the same underlying theory, but they are applied in different ways. Insights into the benefits and limitations of each approach suggest potential future research focuses, which can further reduce the uncertainty associated with dust devil dust entrainment. The potential impacts of dust devils on the climates of Earth and Mars are discussed on the basis of the presented research results

Dust flux within dust devils: Preliminary laboratory simulations

Laboratory simulations using the Arizona State University Vortex Generator (ASUVG) were run to simulate dust flux in dust devils. These tests used particles 2 μm in diameter and 2600 kg m−3 in density, and the results were compared with data from natural dust devils on Earth and Mars. Typically, the cores of dust devils (regardless of planetary environment) have a pressure drop of ∼0.2–1.5 percent of ambient atmospheric pressure. Core pressure drops in our experiments ranged from ∼0.01 to 5.00 percent of ambient pressure (10 mbar Mars cases and 1000 mbar for Earth cases). Flux experiments were run at vortex tangential wind velocities of 1 to 42 m s−1; typically ∼35–50 percent above threshold values for the particles used. Dust flux was determined by time averaged measurements of mass loss for a given vortex size. Dust fluxes of ∼10−3 kg m−2 s−1 were obtained, similar to estimates for flux for dust devils on Earth and Mars, regardless of core size. Vortex strength appears to be closely related to the strength of the pressure drop in the core (ΔP) and is less determined by size of the vortex. This is critical in scaling the laboratory results to natural dust devils

Giant Planet Observations in NASA’s Planetary Data System

While there have been far fewer missions to the outer Solar System than to the inner Solar System, spacecraft destined for the giant planets have conducted a wide range of fundamental investigations, returning data that continues to reshape our understanding of these complex systems, sometimes decades after the data were acquired. These data are preserved and accessible from national and international planetary science archives. For all NASA planetary missions and instruments the data are available from the science discipline nodes of the NASA Planetary Data System (PDS). Looking ahead, the PDS will be the primary repository for giant planets data from several upcoming missions and derived datasets, as well as supporting research conducted to aid in the interpretation of the remotely sensed giant planets data already archived in the PDS